In the construction of mechanical systems, a newly installed or repaired fluid transfer system or system component, as for example a building plumbing or sewage system, or a drain system between floors of a multi-floor building, must frequently be isolated from the a larger system sewage service line until the plumbing construction is tested and inspected, by subjecting the system to a fluid pressure test to locate any leaks, and often certified for compliance with building code requirements. For example, it is common practice within the construction industry to place an outlet end of a newly installed sewage conduit of the building at a juncture near an inlet to a sewage service line. During installation, these two lines are capped and not connected. Where these two lines would otherwise meet, each line is capped off until testing and inspection are complete. As a result of usual construction techniques, the juncture is frequently buried before the tests are performed. After the testing and inspection are complete, the connection site is re-excavated, the caps removed, and a secure connection of the two lines is made. The difficulty of making such tests is often aggravated by the fact that some portion of the system is embedded in a wall or other location difficult of access. For example, in a multi-floor building it is often necessary or convenient to test a drain line on a floor-by-floor basis, before finishing walls covering the drain line, as once wall covering the drain line has been installed and allowed to set, it is generally either exceedingly difficult or impossible to access the drain system or a drain access port. Thus, a vexing question has been posed by the need to seal a localized portion of a drain system or other plumbing or fluid installation system to accommodate testing.
Various patents have been issued disclosing test or isolation valve assemblies used in the inspection of drain systems prior to connection of the systems to sewer lines.
Sullivan, U.S. Pat. No. 4,429,568, discloses a closure plug for pressure testing a liquid drain and vent plumbing type system. Sullivan uses a clean-out Y for access to open the plug plate assembly.
Cohen, U.S. Pat. No. 1,720,819, discloses a test tee having a tapered gate which closes off a house drain pipe from a drainage system. After the test has been completed, the gate is removed from the test tee and the resulting opening in the tee is closed by a cover plate.
Tagliarnio, U.S. Pat. No. 4,542,642, discloses a test tee having a plug which is a removable blocking disk. The blocking disk engages a ledge in the test tee and seals the drainage system. The diaphragm is accessible and removable through an access means.
Roberson, U.S. Pat. No. 4,658,861, discloses a pneumatic plug inserted though a clean-out tee to block off a house service line to the main sewer line.
Kennedy, U.S. Pat. No. 1,948,220, discloses a test plumbing system using a flap valve which is pivoted at an upper side of the valve seat. The flap valve is held in position by a valve adjusting rod.
Barber, U.S. Pat. No. 4,602,504, shows a permanently installed test fitting in which a seal diagram has a frangible, removable portion which may be broken away from the diaphragm and removed to permit service use of the system. A portion of the seal diaphragm remains permanently in the conduit with its edge exposed.
These references relate to the general field of disclosure of this invention but many suffer from the permanent presence of apparatus in the conduit which can catch refuse and cause pluggage.
More recently, U.S. Pat. Nos. 4,848,155, 4,936,350, 5,033,510, and 5,163,480 to Huber have disclosed various apparatus for isolating and testing plumbing installations. It has been noted, however, through usage of the devices described therein, that improvements might be made in the effectiveness of the seal in the test baffle and in means and method for removal of the baffle after the test has been completed. It has also proved possible to improve the flexibility of the baffles disclosed therein, without sacrificing the strength or pressure-resistant capabilities of the baffles, in order to facilitate easier and more efficient removal of the baffles from the fluid line following testing.
Other attempts have included glued-in or molded "cookies" to seal flow within a pipe, in the same general manner as the baffles described in the Huber references above, and inflatable balloon inserted into the fluid line and filled with air or water to block flow. "Screw-in" threaded type plugs have been tried as well, as have dual-plate devices comprising a pair of flat plates attached through their centers by a coaxial tightening device. But glued or molded cookies are often inconvenient to use, and after removal leave behind portions of the baffle which thereafter permanently block part or all of the flow within the fluid line; and they also not infrequently get stuck themselves on removal, requiring dismantlement of the fluid line itself or causing permanent flow obstructions. Inflatable balloons rarely seal the fluid line effectively, especially under moderate or high pressures, such that leakage is a common and continual problem, and testing is rarely fully effective--and typically messy or hazardous, as leaked fluid must be cleaned up or (in the case of gasses) is irretrievably introduced to the atmosphere. Threaded plugs rarely allow testing of an installed system in the form in which it will be used, thus providing at best incomplete test results; and dual-plate devices, which generally comprise substantially rigid plates having flexible polymeric perimeters, often seat themselves on dirt, rust, and other irregularities or obstructions within the fluid line, resulting again in leakage and incomplete or inaccurate testing as well as clean up or environmental hazards.
Thus, there exists a need for a system for the non-destructive testing of the fluid tight integrity of an installed fluid transfer line comprising a removable test baffle and having improved sealing effectiveness between the test baffle and the fluid line, improved means and method for removal of the baffle from the fluid line following completion of the testing, and improved baffle flexibility without reduced strength or pressure resistant capability. There is a further need to provide these objects in a system adapted for the facilitating such testing without danger of permanently fouling or obstructing the drain system.